Posts Tagged ‘Autumn’

The last four weeks have flown by and the final BBC Autumnwatch Live show will be broadcast from Westonbirt Arboretum this Friday, 28th October.

As the focus for this week’s show is woodlands, Westonbirt Arboretum will have a chance to explore different aspects of the tree collection in more detail.

Following on from filming the visual tree health inspections last week, Mark and Dan from Westonbirt’s tree team ventured out with the Autumnwatch crew to film the second half of the story – the use of technology in tree inspections.

Accompanying Mark and Dan were the team from Tree Surveys with the picus sonic tomography used to accompany visual inspections with a picture of the decay.

The picus sonic tomograph is a non-invasive tool for assessing decay in trees. It works on the principle that sound waves passing through decay move more slowly than sound waves traversing solid wood. By sending sound waves from a number of points around a tree stem to a number of receiving points, the relative speed of the sound can be calculated and an image of the cross-section of the tree can be generated.

Chris Packham spent the morning with the team as they set up the tomography, scanned the tree and made the decision on whether to fell or manage the tree in the collection.

Felling a tree is not a decision taken lightly as often the tree is very old and can be an original Holford planting. However, sometimes for health and safety reasons it is necessary. The felled tree will not go to waste however – almost all the wood material is reused, either around the arboretum as woodchip or sold through the Friends of Westonbirt Arboretum wood sales.

Around the site other activity has been underway, including some night filming of owls, the conclusion of several weeks of lapsed time filming and a look at autumn colour. We are looking forward to seeing the final show and will be sad to see the Autumnwatch team leave (they can come back any time!).

You can help to support the work undertaken by the tree team at Westonbirt Arboretum by sending a gift via Just Text Giving to the Friends of Westonbirt Arboretum.
Text a gift of up to £10 by sending the Just Text Giving Code TREE33 followed by the amount you want to donate to 70070. Find out more by watching this film on Westonbirt Arboretum’s YouTube Channel.

With two great BBC Autumnwatch Live shows completed from the Great Oak Hall at Westonbirt Arboretum, and the Autumnwatch team onsite to get ready for another packed programme tonight, attention here is turning towards week 4 (28th October) when the focus will be on the Cotswolds and will look at the arboretum in more detail.

This week, Mark and Dan from our tree team have been filming with Autumnwatch for next week’s show. They’ve been looking at tree health at the work undertaken by the Forestry Commission at Westonbirt Arboretum to manage tree pests and disease.

Mark and Dan visited a few trees on their target list with the crew to talk them through the stages of disease in the specimen and discuss their next course of action. In some cases trees have to be felled and in others they can continue to be managed in the collection for several years.

Mark and Dan will show how they test the trees and use technology to investigate the depths and progression of fungus and disease. They even hope to show how, if nothing can be done to save the tree, it is felled and used for many other purposes. Filming will continue next week, so tune in on 28th October for the final piece.

This week, early visitors to the arboretum on Thursday will also have seen a hot air balloon above the Old Arboretum. This balloon did in fact contain Martin Hughes-Games, looking at autumn colour and the trees of the arboretum from above!

Autumn is a spectacular time of year at Westonbirt. This photo-packed blog will take you through the weekly highlights of what’s looking good and where. Photographs featured here have been taken in the few days prior to publication. Visit the Forestry Commission website for more information about what’s happening at Westonbirt during autumn.

Many of you may have noticed that after an initial early start to autumn, widely reported in the press, things are now going at rather a sedate pace. For us at Westonbirt, this means that although we had a dazzling display of colour from our maples during the first week of the autumn colour watch blog and continue to see the fruits and berries I wrote about last week, further developments to autumn colour are happening much more gradually than we had perhaps anticipated.

It seems that whilst autumn came early to some of Westonbirt’s trees, there are many still to turn. All over Silk Wood you’ll see the contrast of the ‘first wave’ of colour and those trees waiting to be spurred on by a frost or two. One of our Tree Team assures us that there are still many more trees to show autumn colour and the specimens that have turned early have done so because of the ‘stress’ caused by the dry weather. The Japanese maples pictured above in Silk Wood (Willesley Drive, National Japanese Maple Collection and The Link) are all good examples of the combination of colour at present.

There are now some lovely variations in leaf colour around. You might expect this from the Persian Ironwood which is famed for its multicoloured leaves during autumn. But in other spots around the arboretum the same is true. The shagbark hickory is on its way to turning bright golden yellow, but at present has leaves that show a combination of yellow and green as a backdrop to its shiny fruit (this one on Main Drive), whilst the maples again show a range of colours. The Korean Acer pseudosieboldianum perched on a grassy bank near Skilling Gate really stands out against the green backdrop of grass and other specimens yet to turn for autumn – a story repeated throughout the Silk Wood.

Although I got rather carried away with Sorbuslast week I can’t resist showing you a few more that are looking fantastic in the Old Arboretum at the moment. They really are worth seeking out for the sheer variety of berry colours and leaf colours, as they now start to turn. Some are absolutely laden with fruit as you can see!

It is also worth keeping an eye out for the quince at the top of Holford Ride, which has a fair crop of fruit – although its branches are a little prickly as I discovered! Viburnums are also in full berry (this one in the Old Arboretum) and there is a good variety of Cotoneaster – you can see this one on Willesley Drive is covered in berries.

Fungi are another fascinating feature of autumn in our woodlands. Above are a selection of images of some of the fungi that are around at the moment. Look out for them in both the Old Arboretum and Silk Wood. If you’d like to get a better knowledge and be able to identify these, how about joining a walk around Westonbirt with Dave Shorten from the Cotswold Fungi Group on 29 October? He’ll be investigating the fungi at westonbirt and their trees.

In previous years Autumnwatch has broadcast its BBC Two Friday evening programmes from the Natural History Unit in Bristol, but this year it has chosen two new homes – Westonbirt, The National Arboretum for October and WWT Slimbridge for November.

From Friday 7 October at 8.30pm on BBC Two, once a week for eight weeks, Autumnwatch will be tracking the very best autumn wildlife action from around the UK. For their time at Westonbirt, the team will work with the Forestry Commission staff, volunteers and the Friends of Westonbirt Arboretum charity to find great stories for viewers to follow.

This week Westonbirt hosted the Autumnwatch press photography shoot and a few media interviews. The presenters, Michaela Strachan, Chris Packham and Martin Hughes-Games posed for the press photos in Silk Wood and spoke to journalists sitting on hay bales in the Silk Wood Barn!

The presenters have their press photos taken.

Michaela talks about her excitement at joining the Autumnwatch team.

We’ve also been working with one of the cameramen in the Autumnwatch crew to find locations to set up lapsed time filming. Several locations around the arboretum will play a part in this. Positions are being chosen to chart the autumn colour chance and capture leaves falling, sunsets and sunrises. At intervals over the next few weeks a camera will film 15 minutes in each position, these different moments captured in time will then be edited together to show the autumnal changes taking place.

Finally we’ve spent time with the production crew finalising locations for the main programme and for Autumnwatch Unsprung. We are also hoping to bring in Powerline, the team who illuminate our trees for the Enchanted Christmas illuminated trail to light up the trees around the studio and outdoor broadcast locations for the evening programmes.

Are autumn colours at Westonbirt appearing earlier than normal? That’s the question prompted by stories in last weekend’s media about the effects a drier spring has had on trees.

On a walk around Westonbirt for BBC Points West, Arboretum Director Simon Toomer and Tree Team Superintendent Mark Ballard explained that whilst there do appear to be a few tentative signs of the famous reds and oranges of autumn, the best is still to come. They explained to presenter Sabet Choudhury that there can be several reasons for these early autumn signs.

The first is of course the weather. A long dry period in spring led to dry soils, which caused stress in some trees. This can have a delayed effect with trees starting to change colour a few weeks earlier than normal (essentially they are winding down for the year a bit earlier as the chlorophyll in the leaves begins to break down). Some beautiful examples of this can be seen in Acer Glade at the moment, where a few of the Japanese maples (Acer palmatum) are showing a mixture of lush green on the underside of the tree and salmon red/ orange on the top of the canopy.

Acer Glade on 22 August

Another reason is tree pests and disease. One particular case people are becoming more aware of is the horse chestnut leaf miner moth (Cameraria ohridella).

Horse chestnut leaf miner moth

The moth caterpillars burrow into the leaves, which become covered with brown patches. In severe cases, the effect can cause the whole canopy to appear as if it has taken an early autumnal turn. The insect arrived in the UK (London) in 2002 and reached Westonbirt Arboretum about four years ago.

Horse chestnut affected by the leaf miner moth

There are a few examples around Westonbirt, but as this is a relatively new tree pest, scientists are still undecided as to how damaging it will be for trees’ long-term health.

The third reason for unusual leaf colour is that the leaves of some maples are in fact bred to produce colour all year round. These varieties can look particularly spectacular in spring and can be found across the Old Arboretum and into Silk Wood.

On the whole though, most trees are still in their full summer leaf-coats and will wait until shortening day lengths tell them that winter is on the way. Then the real botanical fireworks will begin. As the nights get colder and the first frosts appear, the autumn colour at Westonbirt will accelerate and explode onto the scene in full force.

You can follow the autumn seasonal trail from the start of September. This year’s trail uses Japanese haiku poetry on each stop that has been written by our Friends and visitors to celebrate our most famous season – just pick up your map from admissions on your visit.

Our Autumn Colour Watch blog begins on 1 October and we hope this will be another exciting tool for tracking the colour changes throughout the arboretum.